Fruit extraction and infusion

ABSTRACT

Extraction, especially of firm fruit such as cranberries, with improved yields of high quality, low tannin juices by using an improved countercurrent extractor employing longitudinal members positioned between adjacent flights and reinfusion of decharacterized, extracted fruit pieces with infusion syrups, such as juices from fruits other than that extracted, to produce a fruit food product of various flavors having a desired level of inherent soluble fruit component, without the need to bleed off spent syrup as a byproduct.

FRUIT EXTRACTION AND INFUSION

Field of the Invention

This invention relates to the extraction and infusion of fruits,especially cranberries, for producing various food products.

BACKGROUND OF THE INVENTION

Countercurrent extractors are used in the fruit processing industry forextraction of juices from solid fruit matter. The extractor includes ascrew conveyor which urges fruit solids in a first direction, whileextraction fluid flows in the opposite direction, extracting juice fromthe solids by osmosis. Other juice extraction methods used in theprocessing of cranberries include processes which utilize presses inconjunction with pressing aids (e.g., rice hulls) to produce a highquality single strength juice. Higher yield processes often utilizeenzymatic treatment at elevated temperature to break down pectin in rawfruit prior to extraction and may result in a juice of substantiallylower quality.

SUMMARY OF THE INVENTION

In aspects of the invention, fruits, especially firm berry fruits suchas cranberries, are extracted by an improved countercurrent extractionapparatus resulting in improved and surprising yields of high qualityjuice, without the need for pressing aids, enzymatic treatments, nonexcessive heating of extraction liquid or extracted juice mixtures orthe fruit itself. Further, because enzymes and high temperatures neednot be used, the fruit maintains substantial physical integrity in adecharacterized form post extraction. The decharacterized fruit, aproduct of the juice extraction process, may be used as a carrier forvarious flavorings by infusing the decharacterized fruit with a flavoredliquid infusion syrup. Particularly, infusion may be achieved with acountercurrent apparatus similar to that used for extraction with thedecharacterized fruit being loaded as a solid and the infusion syrup,carrying the flavoring, introduced in a countercurrent fashion. Theresulting infused food product, still maintaining substantial physicalintegrity of the original raw fruit, provides unique flavors by virtueof the various infusion fluids possible, such as fruit juices fromfruits other than the fruit decharacterized. The infused fruit productmay also maintain the characteristic flavor of the fruit itself to adesired degree.

In various aspects, a sequential, two-step process, extraction followedby infusion is taught herein, that provides particular advantages,especially over processes which simultaneously extract and infuse bysoaking fruit in a liquid infusion syrup. In the latter processes,control over the level of natural or inherent soluble fruit component(the composition of materials that contribute to characteristic fruitflavor, including soluble solids such as combinations of sugars andother components, present in the fruit at natural relative levels) inthe infused fruit product can be achieved by adjusting the ratio ofinfusion syrup to fruit, in order to extract the requisite amount ofinherent soluble fruit component into the infusion medium, discharging afraction of the medium as a relatively low value spent syrup byproductand recycling the remaining fraction to infuse and extract more fruit.Recycling the spent syrup in its entirety causes the level of inherentsoluble fruit component in the infusion syrup feed to asymptoticallyapproach that of the fruit feed over time as the syrup is cycled throughsuccessive batches or a continuous flow of fruit and renders controlover the formulation of the infused fruit product at any target level ofinherent soluble fruit component below that characteristic of the fruitvirtually impossible.

In the two-step process, on the other hand, the level of inherentsoluble fruit component in the infused product can be controlled by thedegree of extraction achieved in the extraction step and the degree ofinfusion of formulated infusion syrup achieved in the infusion step.Preferably, most of the inherent soluble fruit component is extractedfrom raw fruit to produce a large volume of high quality juice of highcommercial value, with a predetermined amount of inherent soluble fruitcomponent retained in the decharacterized fruit so that it maintainspartially the natural fruit flavor. In the infusion step, the infusionsyrup is formulated with inherent soluble fruit component (e.g. by usingjuice or juice concentrate) and non-inherent components (e.g. sugars,acids and/or other flavorings and components not present in the naturalfruit or not present at the same relative levels as in the naturalfruit) in such a manner as to control the formulation of the infusedfruit product with respect to its inherent soluble fruit componentwithout the need to bleed off spent syrup as a byproduct of the process.Preferably, there is no net extraction of the inherent component intothe infusion media in the infusion step, i.e., the infusion syrup isformulated such that the level of inherent fruit component is equal toor greater than that in the decharacterized fruit. In preferredembodiments, the infusion is carried out with a countercurrentapparatus, and the spent syrup is Concentrated to remove excess waterand recycled in its entirety.

For example, raw fruit is extracted such that post extraction thedecharacterized fruit contains a small amount, e.g. 1% by weight, ofinherent soluble fruit component and a large amount of the extractionfluid, typically pure water. The infusion syrup is formulated such thatthe level of inherent soluble fruit component in the infusion syrup isapproximately 1% by weight; equal in concentration to the level in thedecharacterized fruit. During infusion, no net infusion or extraction ofinherent soluble fruit component occurs. The spent syrup exiting theinfuser is a blend of inherent and non-inherent soluble componentsdiluted by water extracted from the fruit. This spent syrup, comprisinga higher relative proportion of inherent fruit component when comparedto the target infusion syrup formulation, can be recovered and recycledin its entirety by concentrating to remove the excess water and addingthe requisite amount of non-inherent components to adjust theformulation in line with the desired infusion syrup feed. If the syrupis formulated to comprise a higher concentration of inherent fruitcomponent than in the extracted fruit, there will be a net infusion ofthe inherent fruit components into the decharacterized fruit. In thiscase, the spent syrup can be recycled in its entirety by concentratingto remove the excess water and adding the requisite amount of inherentfruit components (e.g., by adding juice or juice concentrate) to adjustthe formulation in line with the desired infusion syrup feed. In eithercase, the syrup can be concentrated without the aid of enzymes to alevel appropriate for subsequent formulation in infusion syrup. Thus,there is no need to bleed off spent syrup as a low value byproduct,since it can be concentrated and then recycled in its entirety withoutadversely effecting the formulation of the infused fruit product.

By contrast, in processes which simultaneously extract and infuse bysoaking fruit in an infusion syrup (as previously discussed), to producean infused product having a low inherent fruit component level only afraction of the spent syrup generated can be recycled. In effect, thelevel of inherent soluble fruit component in the infused product canonly be controlled by removing the requisite amount of inherent solublefruit component in spent syrup as a low value byproduct.

The invention is therefore of a particular economic advantage since theinherent fruit component which needs to be removed from the fruit (inorder to control the formulation of the infused product) is removed upfront, prior to infusion, as a high value high quality fruit juice.Process costs are also significantly reduced by the more efficienthandling of spent infusion syrup. Further, this feature is of particularimportance for infusion of high-acid fruits, such as cranberries, whichrequire low controlled amounts of inherent soluble fruit component toenhance sweetness and make the infused fruit product more palatable butstill reminiscent of cranberry flavor.

"Decharacterized fruit" as used herein refers to whole fruit or fruitpieces that have been subjected to extraction such that at least 50% ofsoluble solids have been removed. "Firm fruit" as used herein are thosewhich resist structural collapse under substantial compression andtypically are extracted in prior processes with the aid of pectinaseenzymes and/or high temperature to increase yield. Examples include,apples, cranberries, cherries and grapes. On the other hand, "softfruits" are easily collapsed. Examples include raspberries, blackberryand the meat of various fruits especially tropical fruits, e.g., kiwi,guava, mango and passion. (Fruits of this type are also typicallyextracted in prior processes with the aid of enzymes and/or hightemperatures to increase yield.) It will be understood that processes ofthe invention may achieve advantages such as improved yield, quality andlower cost with many fruits. All percentages herein are by weight unlessotherwise indicated or apparent.

In a first aspect, the invention features a countercurrent apparatus foruse with fruit solids that has an elongate housing in the form of atrough or tube with an inlet at or adjacent one end and an outlet at oradjacent the other end. A screw conveyor with a substantially helicalflight is disposed within the housing. The flight is rotatable about itslongitudinal axis for moving fruit solids which have been introducedinto the housing through the inlet from the one end to the other end ofthe housing. Means are provided for introducing liquid into the otherend of the housing in a manner such that introduced liquid will flowalong the housing to the one end thereof and counter current to thefruit solids. A drive means causes the screw conveyor to rotate forproviding a net forward motion of the fruit solids from the one end tothe other end. Means are also provided for withdrawing liquid from thehousing at a point at or adjacent the one end thereof. The apparatus ischaracterized by a screw conveyor that includes a series of narrowlongitudinal members parallel to the conveyor axis positioned betweenadjacent flights.

Various embodiments include the following features. The longitudinalmembers are radially positioned from the periphery, preferably, about10% to 70% the distance from the periphery to the axis of the flights.There are 1 to 12 longitudinal members per square foot of flight area.The longitudinal members are positioned in a circumferential patternabout the axis of the flights. Two sets of members are provided atdifferent radii from the axis. One set of longitudinal members areprovided at a radius of about 25% the distance from the periphery ofsaid flight to the axis and a second set of longitudinal members at aradius about 50% the distance from the periphery to the axis of saidflight. The longitudinal members may be relatively rigid wires or rodswith a diameter in the range of 0.032 to 0.500 inches. The direction ofrotation of the screw conveyor is intermittently reversed.

In another aspect, the invention features extracting juice from fruit byproviding raw fruit in a dimensionally stable form, penetrating the skinof the fruit to expose the inside of the fruit, unprotected by skin, andtreating the fruit with a liquid in a countercurrent apparatus byadvancing the fruit along a path while flowing the liquidcountercurrently to the advancing fruit and uniformly, continuouslytumbling the fruit while treating the fruit with the liquid andmaintaining a process temperature of about 75° F. or less duringextraction, and collecting the extract from the fruit.

In another aspect, the invention features treating fruit by providingraw fruit, penetrating the fruit to expose the inside of the fruit,unprotected by the skin, countercurrently extracting juice from thefruit with an extraction liquid to provide extracted fruit, collectingthe extract from the fruit, collecting the extracted fruit, subjectingthe extracted fruit to countercurrent infusion with an infusion liquidto provide an infused fruit, and collecting the infused fruit.

In another aspect, the invention features a method for processing fruitby providing raw fruit, penetrating the fruit to expose the inside ofthe fruit, unprotected by the skin, extracting the fruit with anextraction liquid to provide decharacterized fruit having a desiredlevel of inherent soluble fruit component, collecting the extract fromthe fruit, collecting the decharacterized fruit, formulating an infusionliquid having inherent soluble fruit component at a level equal to orgreater than the decharacterized fruit, infusing the decharacterizedfruit with the infusion liquid without net extraction of the inherentsoluble fruit component from the decharacterized fruit, collecting thespent infusion liquid after infusion, concentrating the spent liquid,recycling the concentrated spent liquid in its entirety for subsequentinfusion, and collecting the infused fruit.

The features of these aspects may be combined. In addition, variousembodiments may include one or more of the following features. The rawfruit is frozen prior to extraction. The residence time of fruit forextraction is greater than about 90 minutes, such as about 120 to 150minutes. The extraction liquid is substantially free of pectinaseenzymes, e.g. the extraction liquid is water. Uniformly tumbling isachieved between the flights of a screw conveyer by passing narrowlongitudinal members positioned parallel to the axis of the screwthrough the fruit. A temperature of about 100° to 130° F. is maintainedduring the infusion step. The residence time of the fruit is about 120to 300 minutes during the infusion. The fruit is cranberry. The methodincludes concentrating the spent liquid by removing excess water,reformulating the infusion liquid by adding a desired amount of inherentand/or non-inherent soluble components to concentrated, spent liquid,and recycling the reformulated liquid in its entirety for subsequentinfusion. The infusion liquid is selected from fruit juice, fruit juiceconcentrate, corn syrup, sugar-water solutions, artificial sweeteners orany combination of the above, and may be fortified with flavorings,vitamins, and/or minerals. The infusion liquid has 60 to 80 brix. Thedecharacterized fruit has been extracted of about 94 to 98% of solublesolids. The decharacterized fruit is infused to about 40 to 55 brix. Theinfused fruit is dried to remove excess water to a water activity of 0.5to 0.55.

In another aspect, the invention features food products made by methodaspects of the invention. The food product may be a decharacterizedcranberry having removed therefrom at least about 90% of its inherentsoluble solids and including therein a flavor syrup.

Embodiments may include the following. The decharacterized fruit piecehas about 94 to 98% of the inherent soluble solids removed. The syrup isa fruit flavor different from the fruit piece. The food product has brixof about 40 or greater. The fruit is a cranberry. The decharacterizedfruit is free from enzyme degradation and substantially maintains thestructural integrity of raw fruit, being untreated by pectinase enzymes.The decharacterized fruit has been extracted of about 50% or more of itsoriginal color (total anthrocyanine content measured by alcoholextraction).

Other aspects, features and advantages follow.

DETAILED DESCRIPTION

We first briefly describe the drawings.

Drawings

FIG. 1 is a side view schematic of a countercurrent extractor;

FIG. 2 is a perspective schematic of a screw conveyor;

FIG. 2a is an end-on view of the screw conveyor of FIG. 2, taken alongthe lines a--a;

FIG. 3 is a flow diagram of a fruit extraction/infusion process;

FIG. 4 is a perspective illustration of a dried infused fruit product;

EXTRACTOR/INFUSER

Referring to FIG. 1, a countercurrent apparatus 10 for use, e.g., as anextractor, includes an elongate troughshaped housing 11 with a helicalscrew conveyor 2 intermittently rotated by a motor means 20, connectedto a shaft 4 on its longitudinal axis. Housing 11 has an inlet hopper 14for the introduction of material to be extracted, particularly rawcranberries, and an outlet 15 at the other end of the trough housing isprovided for removal of extracted fruit pieces. The hopper 14 isdisposed above the lower end of the screw which is inclined slightlyupwardly at angle Θ. A charging line 17 is provided for chargingextraction liquid, typically pure water, into the housing 11 and adischarge line 16 for the discharge of liquid extract, a mixture ofextraction liquid and juice. The trough temperature may be controlled(e.g., by heating or cooling with a circulating water jacket (not shown)positioned about the trough) to control the process temperature.Alternatively or in addition the temperature of the fruit or extractionliquid may be preselected prior to introduction to the extractor. Thescrew conveyor is operated by intermittently reversing the direction ofrotation of the screw. The reversal helps the relatively compacted massof matter being extracted to be opened up enhancing the penetration ofextracting liquid. Other details of a suitable countercurrent extractorare described in U.S. Pat. No. 4,363,264, the entire contents of whichare hereby incorporated by reference. Commercially available fruitextractor units (e.g., CCE Model 275, Howden Equipment Services Pty,Ltd., Sydney, Australia) may be modified and operated with beneficialresults as described further below.

Referring to FIGS. 2 and 2a, the screw conveyor 2 includes a series ofvertical, helical flights 5, having wire or rod longitudinal members 8positioned between adjacent flights and extending longitudinallygenerally parallel to the conveyor shaft 4 which has an axis A(corresponding to the axis of the flight). As shown particularly in FIG.2a, the wire members 8, may be tied to slits 7 of the flights 5.Typically, the wires are positioned at least about 10 percent andpreferably no more than about 70 percent the distance from the outerperiphery of each flight to the axis A and equidistantly in acircumferential pattern. The wires must be stiff enough to pass throughthe fruit mass without excessive bending to cause the fruit to uniformlytumble along the length between the flights of the conveyor as the shaftrotates. In particular embodiments, (employing CCE Model 275), a set ofwires is positioned at d_(s), about 1.5 inch from the periphery forflights of 10.8 inch diameter (wires positioned about 25% of thedistance from the periphery to the axis), and three wires are used of adiameter with approximately 0.06 inch. (The diameter of shaft 4 is about2.9 inches.) An optional second set of wires 8' (FIG. 2a only) may beprovided at a distance of about 3 inch from the periphery (about 50% ofthe distance from the periphery to the axis). In some embodiments,especially with larger flights, multiple circumferential sets of wiresmay be provided at various radii between the axis and periphery. In someembodiments, the wires might be positioned closer to the axis betweenflights near the raw fruit inlet 14 than between flights near theextracted fruit outlet 15. Positioning the wires further from the axiswithin the specified range has a greater tumbling effect near thedecharacterized fruit outlet 15 where the fruit is usually morecompacted. Typically, about 1 to 12 wires per square foot of flight areaare provided. Preferably, the longitudinal members are positionedequi-distantly radially and circumferentially. Preferably, longitudinalmembers are provided between adjacent flights for the entire length ofthe conveyor.

As further described in the Examples below, it has been found that, byemploying longitudinally extending members, such as wires 8, improvedefficiency in extraction of juices from fruit may be achieved, even inthe case of firm berry fruits such as cranberries. In addition, it hasbeen found that a countercurrent apparatus, as described, can be usedfor the infusion of fruit decharacterized by extraction to provide newfood products. In this case, extracted, decharacterized fruit is placedin the inlet hopper 14 and an infusion liquid carrying a desired flavoris introduced through charging line 17. The infused fruit product exitsoutlet spout 15. The use of members 8 also improves efficiency of theinfusion.

Preferred and typical parameters for operation of a countercurrentapparatus with the improved conveyor for extraction of cranberries aregiven in Table I below and parameters for infusion of decharacterizedcranberries with an improved conveyor are given in Table II below."Extract level" and "infusion liquid level" refers to the depth of theseliquids compared to the screw flight nearest the discharge line 16. The"process temperature" is the temperature of the liquid in the trough.(The temperature of liquid in the trough is typically measured about onehalf the length of the trough from the fruit inlet and is generally thehighest temperature along the trough in cases where unheated fruit andliquid are introduced at either end.) The screw rotation is the speed atwhich the screw rotates in any direction (e.g. during intermittentrotation). The water/fruit and infusion syrup/fruit feed rate ratio arethe weight ratios of the rates at which these components are fed to thetrough. For operation with a preferred countercurrent apparatus, CCEmodel 275 modified as discussed, the berry weight in the trough andberry feed rate are also given. (It will be understood that desired feedrates for liquid and fruit for an infusion or extraction apparatus ofany size may be calculated from the tables below, knowing the troughcapacity of the particular unit used and the range of feed ratiosspecified below.)

                  TABLE I                                                         ______________________________________                                                           Range   Typically                                          ______________________________________                                        Process Variable                                                              inclined ange Θ (degrees)                                                                    2 to 6    4                                              process temperature (deg. F.)                                                                      45 to 75  65                                             fruit residence time (minutes)                                                                     30 to 180 135                                            screw rotation (rpm) 1 to 4    2                                              water/fruit feed rate ratio                                                                        1:1 to 4:1                                                                              2.5:1                                          (weight ratio)                                                                extract level        50 to 70% 60%                                            (% of flight diameter at discharge)                                           For CCE Model 275                                                             Berry weight in Trough                                                                             70-80     75                                             (lbs)                                                                         Berry feed rate      23-160    33                                             (lbs/hr)                                                                      ______________________________________                                    

For infusion of cranberries, the countercurrent apparatus is preferablyoperated with the parameters in Table II below.

                  TABLE II                                                        ______________________________________                                                            Range   Typically                                         ______________________________________                                        Process Variable                                                              inclined angle θ (degrees)                                                                    2 to 6    4                                             process temperature (°F.)                                                                    100 to 130                                                                              110                                           fruit residence time (minutes)                                                                      120 to 300                                                                              240                                           screw rotation (rpm)  1 to 4    2                                             infusion liquid/fruit feed rate ratio                                                               2:1 to 6:1                                                                              3:1                                           (weight ratio)                                                                infusion liquid level 50 to 70% 60%                                           (% of flight diameter at discharge)                                           For CCE Model 275                                                             dicharacterized fruit weight in Trough                                                              65-75     70                                            (lbs.)                                                                        decharacterized fruit feed rate                                                                     13-38     17.5                                          (lbs/hr.)                                                                     ______________________________________                                    

Process

Referring now to FIG. 3, a flow diagram is shown of a preferred processemploying extraction followed by infusion and preferably usingcountercurrent apparatus as described above with respect to FIGS. 1-2a.(It will be understood that other extractors and infusers may be used inthe process.) The process will be described for use with cranberries,although it may be adapted for use with other fruit, especially firmfruit.

Whole raw fruit which has been bulk frozen is provided to a cleaningstage 40 to remove debris such as twigs, leaves, soil, etc. and thenconveyed to a sorting stage 42 which sorts fruit of a selected size,within a selected deviation, and removes rotten or damaged fruit. Thefreezing of the fruit prior to further processing is believed to be animportant aspect of the invention, in that, upon rethawing, the fruit isstructurally more susceptible to juice extraction. Again, thedeleterious effect on juice quality associated with high temperaturetreatment (or the use of enzymes) is avoided. The frozen fruit is in theraw state, without having been boiled or otherwise cooked prior toprocessing. The frozen fruit (e.g., initially at about 25° F.) thawsnaturally upon exposure to the flume water (e.g., about 55° F.) and theextraction trough (e.g., about 65° F.) without any substantial heating.As discussed above, generally, exposure to heat is avoided especiallyprior to and during extraction, so that the fruit is not exposed toaverage process temperatures above about 75° F.

Control over the average size and standard deviation of the raw fruit isalso believed an important attribute of the present process whereas auniformly sized infused product ultimately results. In the case ofcranberries, preferably the sorted berries are 16 to 20 millimeters (mm)in diameter with a standard deviation of about 1 mm. The size-selectedfruit is later passed to a dicer stage 44 (Model RG-6, A. B. HalldeMaskiner, Kista, Sweden) which slices the berries to expose the innerpulp of the fruit unprotected by the skin. The whole cranberries arepreferably cut in half to provide slices between 8 to 10 millimeters inwidth, although other skin penetrating treatments such as scarifying mayalso be used.

The sliced fruit is transported by means of a flume to a separationstage 46, including a vibrating screen separation apparatus (ModelLS24S444, Sweco, Inc., Florence, Ky.) which separates the sliced fruitfrom the flume water, recycling water back to the flume, and removesseeds at a seed collection stage 48. The sliced fruit is then providedto the solid input 51 of an extractor stage 50 which employs acountercurrent extractor which may be as previously described withrespect to FIGS. 1-2a and operated within the limits of Table I. Theliquid input 53 to the extractor is the extraction liquid, typicallypure water without added enzyme, from a supply 52. The liquid output 54of the extractor stage is an enzyme-free, high-quality extract mixtureof extraction liquid and fruit juice which exhibits desirable qualitiessuch as low tannin content. The extractor, preferably operating at lowtemperatures, but at high efficiency, avoids the detrimental effects onjuice quality normally associated with higher temperature extraction,such as reduced shelf-life characteristics, burnt notes in the juiceflavor and higher tannin levels. The raw juice extract from theextractor stage liquid output 54 is further treated, first in aseparation stage 56, using a vibrating screen separator (Model LS24S444,Sweco, Inc., Florence, Ky.) which collects in collection stage 66 anyremaining seeds and solids. The juice extract is further treated in adepectinization stage 58 in which pectinase enzyme is provided from asupply 60 and mixed with the juice extract. The enzyme, in small amounts(between about 0.01 and 0.1 percent) clears the juice extract of pectinin preparation for a filtration stage 62. Whereas the juice has alreadybeen extracted from the fruit, the enzyme plays no substantial role inthe overall extraction process and thereby only small amounts of theenzyme, known to be an expensive process ingredient, need be used.Filtration at stage 62 is achieved by means of a microfilter of 0.1-0.5micron pore size. The filtered juice extract is further treated at areverse osmosis stage 64, (Model BRO, Paterson Candy, Inc.) where thejuice extract is passed through a membrane system under pressure toconcentrate the final juice product, which is collected at stage 65 asis the excess water at stage 68. Typically, the final juice product isof about 18 brix. The cranberry juices produced by the process typicallyhave a tannin content less than about 1900 mg/L, e.g. about 1700 mg/L(measured at 7.5 brix).

Decharacterized cranberry pieces, exiting the solid output 71 ofextraction stage 50, are typically characterized by the removal of about96 percent of the soluble solids and about 80 to 96 percent of thecolor. At higher temperatures, for example, at 85° to 105° F. virtuallyall of the color can be removed from the decharacterized fruit, ifdesired. Extraction time can be extended to achieve the same end.Decharacterized fruit lacking all of its original color may beadvantageous for producing infused fruit products that are to take on acolor other than that of the original fruit. Similarly, for producing aninfused product that is characteristic, in appearance, of a cranberry,an amount of the color suggestive of the cranberry is maintained in thedecharacterized fruit.

The decharacterized fruit is supplied to an infusion stage 72 includinga countercurrent apparatus similar to that used at the extraction stage50 and as discussed with respect to FIGS. 1-2a, operated in the rangesgiven in Table II. Liquid input at the infusion stage 72 is the desiredinfusion liquid such as sugar-water (e.g., fructose) solution, highfructose corn syrup, white grape juice, strawberry juice, raspberryjuice, blueberry juice, apple juice and their concentrates. Theseinfusion liquids may include flavoring, e.g., spices such as cinnamonand may be fortified with vitamins, e.g. ascorbic acid, and/or minerals,e.g. iron. The infusion liquid typically has a sugar level of about 72brix and is provided from a continuous process loop which mixes thespent infusion liquid from the liquid output 74 from infusion stage 72with syrup from a supply 76 which is then treated in a vibrating screenseparator 78 (Model LS24S444, Sweco, Inc., Florence, Ky.) to remove andcollect seeds and fines at a collection state 80. The spent infusionmixture is then concentrated at concentration stage 82 including a watercollection stage 84 and finally, the liquid is treated at a blend stage86 which may include input from an infusion sugar supply 88, beforebeing recycled to the liquid input 90 of infuser 72 as the infusionliquid. As discussed above, the infusion liquid can be formulated toinclude a desired amount of natural or inherent soluble fruit component,equal to or greater than the amount present in the decharacterized fruitso that no net extraction of inherent soluble fruit component into theinfusion media occurs during infusion. The infused fruit product has thedesired level of inherent soluble fruit component and the spent infusionliquid is concentrated and recycled in its entirety.

The infused fruit product exiting the infusion stage at the solid output92 is passed to a screening stage 94 at which the infused fruit productis separated from excess infusion liquid coating the solid product,which is collected at collection stage 96. The excess syrup may beprovided to syrup supply 76 for recycling to the infuser 72. The infusedfruit product is then provided to a dryer stage 98 which passes forcedair through the infused fruit product to remove water at stage 100.Drying temperature is typically in the range of about 180° to 200° F.for about 120 minutes using a conventional forced air fruit dryer. Thedried, infused fruit product is next passed to an oiler stage 102 whichincludes an oil supply 104 from which vegetable oil or the like isapplied to the fruit product to enhance flowability. A screen separator(Model LS24S444, Sweco, Inc., Florence, Ky.) 106 with a stage 108 isused for collection of any fines and waste. The final dried infusedproduct, maintaining substantial physical integrity of the originalfruit, is collected in a collection stage 110 from which it may be bulkpackaged. The dried product preferably has a sugar level of about 88brix.

Referring to FIG. 4, a dried infused cranberry fruit product accordingto the invention is illustrated. The fruit product maintains substantialstructural integrity of the original cranberry including the skin 114and typically a portion of the original color of the cranberry. Theflavor of the fruit product however is that of the infusion syrup whichmay be of many varieties including a controlled amount of flavor of theoriginal fruit. A coating may be applied which also contributes toflavor and/or nutrient value.

The invention will be further described by way of the followingexamples.

EXAMPLE 1

The process described in FIG. 3 can be operated using raw frozencranberries as the fruit input. In the extraction stage (referring aswell to Table I) the process temperature is about 65° F., with aresidence time of about 135 min., a screw rotation of 2 rpm, awater/berry weight ratio of 2.5:1 and extraction liquid (water) level of60%. The extraction stage produces a decharacterized fruit with 0.3%inherent soluble fruit component. The infusion stage (referring as wellto Table II) can employ an aqueous blend of sucrose (68.0%) andcranberry fruit components (4.0%) as the infusion syrup and acountercurrent apparatus identical to that in the extraction stage,operated at a temperature of about 110° F., residence time of about 180min., screw rotation of about 2 rpm, infusion liquid to berry weightratio of about 4:1. The spent infusion syrup can then be collected to beconcentrated and reformulated as discussed herein. Target inputs andoutputs from the various stages are summarized in Table III, below. Allcalculations are normalized to 8 lbs. of fruit soluble solids per 100lbs. of cranberries.

                                      TABLE III                                   __________________________________________________________________________    PROCESS                                                                       STAGE                           CONCENTRATION                                 (FIG. 3)                                                                            MATERIAL            AMOUNT                                                                              (WATER PHASE)                                 __________________________________________________________________________    40/42 FROZEN SORTED CRANBERRIES                                                                         100.0                                                                            LBS                                                                              8    brix                                     44    FLUME RECYCLE (WATER)                                                                             900.0                                                                            LBS                                              48    CRANBERRY SEEDS     0.3                                                                              LBS                                              51    SLICED CRANBERRIES  99.7                                                                             LBS                                              53    WATER               250.0                                                                            LBS                                              54/56 JUICE EXTRACT/WATER 257.7                                                                            LBS                                                                              3    brix                                     60    ENZYME              0.1                                                                              LBS                                              65    CRANBERRY JUICE/WATER                                                                             43.0                                                                             LBS                                                                              18   brix                                     66    TRASH (SEEDS/FINES) 0.1                                                                              LBS                                              68    WATER               214.7                                                                            LBS                                              71    EXTRACTED DECHARACTERIZED                                                                         92.0                                                                             LBS                                                                              0.3  brix                                           SLICES                                                                  74    SPENT SYRUP         256.0                                                                            LBS                                                                              55   brix                                     80    TRASH (SEEDS/FINES) 0.1                                                                              LBS                                              84    WATER               37.9                                                                             LBS                                              88    INFUSION SUGAR      61.0                                                                             LBS                                              90    INFUSION SYRUP      284.0                                                                            LBS                                                                              72   brix                                     92/94 INFUSED FRUIT PIECES                                                                              120.0                                                                            LBS                                                                              55   brix                                     96    EXCESS SYRUP        5.0                                                                              LBS                                                                              55   brix                                     100   WATER               41.6                                                                             LBS                                              104   OIL                 0.1                                                                              LBS                                              108   FINES               17.5                                                                             LBS                                              110   DRIED INFUSED FRUIT SLICES                                                                        56.0                                                                             LBS                                                                              88   brix                                     __________________________________________________________________________

The cranberry juice product provided by the process at stage 65typically has a tannin content less than about 1900 mg/L (at 7.5 brix),and has no noticeable off-flavors associated with heat abuse. As thetable indicates, the process is highly efficient for the production ofcranberry juice with 43 lbs. of juice (at 18 brix) being produced from100 pounds of cranberries. This corresponds to 96% recovery on a weightbasis (FSP, fruit soluble solid pounds, i.e., percent fruit solublesolid recovery based on weight of fruit soluble solid in raw fruitcompared to that recovered in the extract). In addition, the processprovided a new fruit product in the way of infused cranberry sliceshaving the sweetened flavor of the infusion syrup.

EXAMPLE 2

The efficiency of juice recovery employing an improved extractor wasillustrated by a series of comparative experiments (experiments 1 to 6)in which process parameters for extraction were varied, as summarized inTable IV below.

                                      TABLE IV                                    __________________________________________________________________________    Process  Experiment                                                           parameter                                                                              1    2   3    4   5    6                                             __________________________________________________________________________    Unit Size                                                                              pilot                                                                              pilot                                                                             pilot                                                                              pilot                                                                             pilot                                                                              commercial                                    Enzymes in                                                                             Yes  No  No   No  No   No                                            Extraction                                                                    Liquid                                                                        Improved No   No  Yes  Yes Yes  Yes                                           Extractor                                                                     (FIGS. 1-2a)                                                                  Residence Time                                                                         90   90  90   135 160  135                                           (min)                                                                         Extraction                                                                             85-115                                                                             85-115                                                                            85-115                                                                             85-115                                                                            69-75                                                                              65                                            Temperature                                                                   (°F.)                                                                  Efficiency                                                                             75   67  84   96  96   96                                            % FSP recovery                                                                Relative 2146 1950                                                                              2381 2292                                                                              1734 1273                                          Tannin Content                                                                mg/L                                                                          __________________________________________________________________________

In Experiment 1, a pilot sized extractor unit (nominal capacity=30kilograms per hour) was used to extract juice from cranberries,employing in the extraction liquid enzymes effective in pectin breakdown(about 0.07-0.15 lbs./100 lbs. feed). The extractor was of acommercially available type (CCE Model 275, Howden Equipment ServicesPty, Sydney, Australia). The efficiency of extraction was approximately75% of available FSP with a relatively high (2146 mg/L, measured at 7.5°brix) tannin content.

In Experiment 2, similar process conditions were employed, with theexception that no enzyme was introduced to the extraction liquid. Theefficiency of extraction dropped to about 67% of available FSP.

In Experiment 3, the extractor unit was modified as described withrespect to FIGS. 1-2a; a series of longitudinally extending wires wereprovided between adjacent flights of the extractor screw. Surprisingly,by employing the improved countercurrent unit, extraction efficiencyincreased to about 84% of available FSP recovery without the use ofenzymes, representing a significant improvement over operation of theconventional extractor (even with the use of enzymes).

In Experiment 4, the improved countercurrent apparatus was operated withextended residence time (135 minutes) compared to Experiment 3 (90minutes). Under these conditions, extraction efficiency increased toabout 96% of available FSP recovery.

In Experiment 5, the extraction temperature was reduced to about 69°-75°F., compared to about 85° to 115° F. used in Experiments 1 to 4 (withthe residence time marginally increased). Surprisingly, the extractionefficiency remained at about 96% of available FSP recovery and theresulting juice product was of improved quality over that of experiments1 to 4, in that the juice exhibited significantly lower tannin levels.

In Experiment 6, the extraction efficiency of a much larger commercialscale extraction unit (CCE model 500, nominal capacity=500 kilograms perhour) was investigated and the results compared to that obtained withthe smaller pilot scale unit used in the previous experiments. The unitemployed an extractor screw modified to include longitudinally extendingwires between adjacent flights and was operated at an extractiontemperature of 65° F., with residence times of about 135 minutes. Theextraction efficiency was similar to that obtained in the smaller unit.

Other embodiments are within the following claims.

We claim:
 1. A method for efficiently extracting from fruit a juice thathas not been exposed to high temperatures, comprising:providing rawfruit in a dimensionally stable form, penetrating the skin of said fruitto expose the inside of said fruit, unprotected by skin, treating saidfruit with an extraction liquid in a countercurrent apparatus byadvancing said fruit along a path while flowing said liquidcountercurrently to said advancing fruit and uniformly, continuouslytumbling said fruit while treating said fruit with said liquid,maintaining a process temperature of about 75° F. or less during saidextracting and, collecting said liquid extracted from said fruit toprovide said juice that has not been exposed to high temperatures. 2.The method of claim 1 wherein the residence time of said fruit duringsaid extracting in said countercurrent apparatus is greater than about90 minutes.
 3. The method of claim 2 wherein the residence time is about120 to 150 minutes.
 4. The method of claim 3 further comprising freezingsaid raw fruit prior to said providing step.
 5. The method of claim 4wherein said extraction liquid is water substantially free of pectinaseenzymes.
 6. The method of claim 1 or 5 wherein said uniformly tumblingincludes tumbling between flights of a screw conveyer by passing narrowlongitudinal members positioned parallel to the axis of said screwconveyer through said fruit.
 7. The method of claim 6 wherein said fruitis cranberry.
 8. A method for processing fruit, comprising:providing rawfruit, penetrating said fruit to expose the inside of said fruit,unprotected by the skin, countercurrently extracting said fruit with anextraction liquid while maintaining conditions, including a lowtemperature, that provide extracted fruit with substantially thestructural integrity of the raw fruit, and a fruit extract that has notbeen exposed to high temperatures, collecting the extract from saidfruit, collecting the extracted fruit, and countercurrently infusingsaid extracted fruit with an infusion liquid while maintainingconditions that provide an infused fruit with substantially thestructural integrity of the raw fruit, and collecting said infusedfruit.
 9. The method of claim 8 comprising freezing said raw fruit priorto said providing step.
 10. The method of claim 8 further comprisingcollecting spent infusion liquid after said countercurrent infusion,concentrating said spent liquid and recycling said concentrated liquidin its entirety for subsequent infusion.
 11. The method of claim 10comprising:extracting said fruit to provide a decharacterized fruithaving a selected level of inherent soluble fruit component, andformulating said infusion liquid to have a level of inherent solublefruit component substantially equal to or greater than said level insaid decharacterized fruit
 12. The method of claim 8 wherein saiddecharacterized fruit has been extracted of about 94 to 98% of solublesolids.
 13. The method of claim 8 wherein said infusion liquid includesa liquid selected from fruit juice or fruit juice concentrate, cornsyrup, sugar-water solutions, and artificial sweeteners or combinationthereof.
 14. The method of claim 13 wherein the infusion liquid isfortified with a material selected from the group consisting ofvitamins, flavorings, minerals, and combinations thereof.
 15. The methodof claim 8 wherein said infusion fruit to about 60 to 80 brix.
 16. Themethod of claim 8 comprising infusing said fruit to about 40 to 55 brix.17. The method of claim 16 further comprising drying said infused fruitto remove water.
 18. The method of claim 17 comprising drying saidinfused fruit to about 40 brix or greater.
 19. The method of claim 17comprising drying said infused fruit to a water activity of about 0.5 to0.55.
 20. The method of claim 8 wherein the extraction liquid is watersubstantially free of pectinase enzymes.
 21. The method of claim 20comprising extracting said fruit by advancing said fruit and flowing anextracting liquid countercurrently to said advancing fruit, whilecontinuously uniformly tumbling said fruit between the flights of ascrew conveyor by passing narrow longitudinal members parallel to theaxis of said conveyer through said fruit.
 22. The method of claim 21further comprising infusing said decharacterized fruit by advancing saidfruit and flowing an infusing liquid countercurrently to said advancingfruit, while continuously uniformly tumbling said fruit between theflights of a screw conveyor by passing narrow longitudinal membersparallel to the axis of said conveyer through said fruit.
 23. The methodof claim 22 further comprisingmaintaining the temperature at about 75°F. or less during said extracting step.
 24. The method of claim 23comprising maintaining a residence time of said fruit of greater thanabout 90 minutes during said extraction.
 25. The method of claim 24wherein the residence time of said fruit is about 120 to 150 minutes.26. The method of claim 25 comprising maintaining a process temperatureof about 100° to 130° F. during said infusing.
 27. The method of claim26 comprising maintaining a residence time of said fruit of about 120 to300 minutes during said infusing.
 28. The method of any one of claims 8,20 or 23 wherein said fruit is cranberry.
 29. A method for processingfruit, comprising:providing raw fruit, penetrating said fruit to exposethe inside of said fruit, unprotected by the skin, extracting said fruitwith an extraction liquid to provide decharacterized fruit having adesired level of inherent soluble fruit component, collecting theextract from said fruit, collecting the decharacterized fruit,formulating an infusion liquid having inherent soluble fruit componentat a level equal to or greater than said decharacterized fruit, infusingsaid decharacterized fruit with said infusion liquid without netextraction of said inherent soluble fruit component from saiddecharacterized fruit, collecting a spent infusion liquid after saidinfusing, concentrating said spent liquid, recycling said concentratedspent infusion liquid for subsequent infusion, and collecting saidinfused fruit.
 30. The method of claim 29 including reformulating saidinfusion liquid by the addition of non-inherent soluble component tosaid concentrated spent syrup.
 31. The method of claim 30 includingreformulating said infusion liquid by the addition of inherent solublefruit component to said concentrated spent liquid.
 32. The method ofclaim 31 wherein said infusing includes countercurrently infusing. 33.The method of claim 32 wherein said extraction liquid is water-free ofpectinase enzymes.
 34. The method of claim 29 or 33 comprising freezingsaid raw fruit prior to said providing step.
 35. The method of claim 34comprising maintaining a process temperature of about 75° F. or lessduring said extracting step.
 36. The method of any one of claims 1, 5,7, 23, 29 or 35 wherein said fruit is cranberry and said extract has atannin content of less than about 1900 mg/L measured at 7.5 brix.
 37. Araw cranberry fruit food product, comprising:a decharacterized cranberryfruit piece having removed therefrom at least about 90% of its inherentsoluble solids and including therein a flavor liquid, said producthaving a brix of about 40 or greater.
 38. The food product of claim 37wherein about 94 to 98% of the soluble solids have been removed.
 39. Thefood product of claim 37 wherein the syrup is a fruit flavor differentfrom the fruit piece.
 40. The food product of claim 37 wherein saiddecharacterized fruit is free from added enzyme degradation,substantially maintaining the structural integrity of the raw fruit,being untreated by pectinase enzymes.
 41. The food products of claim 37wherein said decharacterized fruit has been extracted of about 50% ormore of its original color.